Question

The interferogram obtained for a spherical mirror in the “null” position in a TwymannGreen interferometer shows only one central dark spot (no dark circular fringes). The spherical mirror is replaced by a perfect parabolic mirror at the same position and with the same radius of curvature R=−100 mm. Assuming the laser beam diameter at the mirror is 20 mm, find the number of dark circular fringes visible in the interferogram.

Answer 1

Problem -Solulion - loomm. Tayman Green Interferometer - Spherical mücey = replaced by perfect parabolic mirros Radius of cureature laser beam diameter at meiros to find numbey of dark cicular frenges, becomes simple when tlo. l) is mention to seluce this the number of dark funges. 2omm. et

Black screen collecting lene cenden lens, test to Source spherical mirar Beam spletter Imaging Systems Twyman Green Interferrometer setup

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